JACC: CARDIOVASCULAR INTERVENTIONS
VOL. 10, NO. 2, 2017
ª 2017 BY THE AMERICAN COLLEGE OF CARDIOLOGY FOUNDATION
ISSN 1936-8798/$36.00
PUBLISHED BY ELSEVIER
http://dx.doi.org/10.1016/j.jcin.2016.11.021
EDITORIAL COMMENT
Drug-Drug Interactions When Switching Between Intravenous and Oral P2Y12 Receptor Inhibitors How Real Is It?* Fabiana Rollini, MD, Francesco Franchi, MD, Dominick J. Angiolillo, MD, PHD
S
witching between 2 platelet P2Y12 receptor
occurs with cangrelor infusion prevents binding of
inhibitors commonly occurs in clinical practice
the active metabolite of clopidogrel to the P2Y12 recep-
(1). Multiple factors, including a patient’s
tor. Given the short plasma half-life of the active
bleeding or thrombotic risk, occurrence of an adverse
metabolite of thienopyridines, it gets rapidly (within
event, socioeconomic issues, results of platelet func-
a few hours) eliminated from the systemic circulation
tion or genetic tests, or physician or patient prefer-
if no binding occurs, translating into no platelet inhib-
ence, among other reasons, may lead to switching of
itory effect (1–3). This DDI can be prevented by admin-
therapy. Indeed, the potential for drug-drug interac-
istering clopidogrel at the end of the cangrelor
tions (DDIs) represents a concern when switching
infusion, which allows a washout of cangrelor while
between platelet P2Y 12 receptor inhibitors. In partic-
clopidogrel is being absorbed, undergoes hepatic
ular, the different pharmacological profiles of these
metabolism, and for its active metabolite to bind
agents have raised unease as to whether switching
with the P2Y12 receptor. On this background, in 3
may lead to enhanced (increasing the risk for bleeding)
large-scale clinical trials with 24,910 patients testing
or mitigated (increasing the risk for thrombosis) P2Y 12
the safety and efficacy of cangrelor in patients under-
inhibitory effects (1,2). Cangrelor, a recently approved
going percutaneous coronary intervention (PCI),
potent intravenous P2Y12 receptor inhibitor, is charac-
clopidogrel was judiciously administered at the end
terized by a rapid onset and offset of action (2,3).
of the cangrelor infusion (5). Accordingly, with the
During the clinical development of cangrelor, a phar-
approval of cangrelor for clinical use, drug-regulating
macodynamic (PD) investigation identified a DDI
agencies specify the importance of clopidogrel loading
when clopidogrel was concomitantly administrated
dose (LD) administration at the end of cangrelor
with cangrelor (4). The high receptor occupancy that
infusion to avoid a DDI (1). Although there are robust clinical and PD data to support the optimal transitioning strategy from
*Editorials published in JACC: Cardiovascular Interventions reflect the
cangrelor to clopidogrel, there are very limited data on
views of the authors and do not necessarily represent the views of JACC:
switching from cangrelor to the more potent oral P2Y12
Cardiovascular Interventions or the American College of Cardiology.
receptor antagonists prasugrel and ticagrelor (1). This
From the University of Florida College of Medicine–Jacksonville, Jack-
knowledge
sonville, Florida. Dr. Angiolillo has received payments as an individual
increasing use of these latter agents, particularly for
for consulting fees or honoraria from Amgen, Bayer, Pfizer, Sanofi, Eli
the treatment of high-risk patients undergoing PCI,
Lilly, Daiichi-Sankyo, The Medicines Company, AstraZeneca, Merck,
gap
is
noteworthy
given
the
ever
Abbott Vascular, and PLx Pharma; for participation in review activities
among whom cangrelor is also more likely to be used.
from CeloNova, Johnson & Johnson, and St. Jude Medical; and has
The results of these PD studies suggest that the tran-
received institutional payments for grants from GlaxoSmithKline, Eli
sition from cangrelor to prasugrel (which like clopi-
Lilly, Daiichi-Sankyo, The Medicines Company, AstraZeneca, Janssen
dogrel is a thienopyridine with an unstable active
Pharmaceuticals, Osprey Medical, Novartis, CSL Behring, and Gilead. All other authors have reported that they have no relationships relevant to
metabolite) should occur at the end of cangrelor
the contents of this paper to disclose.
infusion to avoid a DDI and ideally 30 min prior to the
Rollini et al.
JACC: CARDIOVASCULAR INTERVENTIONS VOL. 10, NO. 2, 2017 JANUARY 23, 2017:130–2
Switching Between P2Y12 Receptor Inhibitors
end of the infusion to allow the smoothest transition
real-world practice. Moreover, this is a rather large PD
(6,7). Ticagrelor, on the contrary, because of its longer
investigation, with platelet reactivity being assessed
systemic half-life (including that of its major metab-
at 7 time points in 110 PCI patients. Most important,
olite), can be given at any time (before, during, or after
the investigators challenged a dogma with regard to
cangrelor infusion) without resulting in a DDI (8). The
the timing of prasugrel administration when cangre-
findings of these PD studies have been taken into
lor is being used. Specifically, they showed that
consideration by drug-regulating agencies when
administering prasugrel at the time of cangrelor bolus
providing recommendations on how to transition from
was not associated with a DDI. The rationale for this
cangrelor to prasugrel and to ticagrelor (1). However,
observation
the fact that these were very small PD studies and not
metabolite is unstable, its half-life is longer than that
is
that
although
prasugrel’s
active
conducted in patients undergoing PCI underscores the
of clopidogrel (10). Therefore, this would provide
need for further investigations on transitioning from
sufficient time for prasugrel’s active metabolite to
cangrelor to prasugrel and ticagrelor.
bind with the P2Y 12 receptor after discontinuation of cangrelor infusion. Accordingly, although not pow-
SEE PAGE 121
ered for clinical outcomes, no safety concerns
In this issue of JACC: Cardiovascular Interventions,
emerged from this analysis. These findings indeed
Hochholzer et al. (9) report the results of the Excel-
represent a paradigm shift and have important im-
siorLOAD2 study, in which the investigators exam-
plications for clinical practice. In fact, the notion that
ined the transition between cangrelor and oral P2Y12
prasugrel needs to be given at the end of the can-
receptor inhibitors (clopidogrel, prasugrel, and tica-
grelor infusion to avoid a DDI, while ticagrelor can be
grelor) in a total of 110 patients (20 patients with
given at any time without incurring in this compli-
clopidogrel, 45 patients with prasugrel and with
cation, inevitably disadvantages the use of prasugrel.
ticagrelor) undergoing PCI (9). Cangrelor bolus and
The results of this study thus provide new insights
infusion were initiated immediately before the PCI
and importantly give more options to physicians on
procedure and continued for at least 2 h or for the
when to administer prasugrel, including in the cath-
duration of the procedure, whichever was longer.
eterization laboratory, when cangrelor is being used.
Patients were then randomly assigned to receive
There are some other aspects that need to be taken
1 of the 3 oral agents. Those who were randomized
into account when interpreting the results of the
to prasugrel and ticagrelor received the LD at the
ExcelsiorLOAD2 study. First, the choice of absence of
same time of the cangrelor bolus, while the clopi-
HPR at 1 h after discontinuation of cangrelor infusion
dogrel group received the LD at the end of cangrelor
as the primary endpoint may be debated. In fact,
infusion. Platelet reactivity was assessed using the
although HPR is a well-recognized marker of throm-
Multiplate Analyzer at 7 time points, and high
botic complications, differences in absolute values of
on-treatment platelet reactivity (HPR) was defined
platelet reactivity could have represented a more
as >468 arbitrary units per min. The primary
sensitive endpoint to discern the presence of a DDI.
endpoint was the comparison of rates of patients
Moreover, given the presence of some PD variability,
without HPR (prasugrel vs. clopidogrel) 1 h after
it cannot be ruled out that at 1 h after discontinuation
discontinuation of the cangrelor infusion. Ischemic
of cangrelor infusion there could have been some
and bleeding outcomes were assessed at 30 days post-
residual effect (3). Thus, a later time point (e.g., 2 h)
PCI. Considered from the other perspective, the rates
would have diminished the chances of this potential
of HPR 1 h after cangrelor infusion were 35%, 6.7%,
confounder.
and 4.4% with clopidogrel, prasugrel, and ticagrelor,
Second, the well-established superior PD potency
respectively. The investigators conclude that a pra-
of prasugrel makes the choice of a comparison with
sugrel LD given at the same time as the cangrelor
clopidogrel somewhat less attractive than a study
bolus
that would have been specifically designed to
can
provide
sufficient
platelet
inhibition
following cangrelor discontinuation (9).
consider
ticagrelor
as
the
primary
comparator.
The investigators should be commended for this
Although the study does provide some encouraging
investigation, which provides important and novel
insights on this comparison, this remains an explor-
insights on switching from cangrelor to oral P2Y 12
atory observation, as the study was not powered for
receptor inhibitors. Importantly, for the first time, all
this assessment.
3 oral P2Y 12 receptor antagonists were investigated in
Third, study arms comprising administration of
a randomized fashion. At difference from most prior
prasugrel and ticagrelor also during and at the end of
PD studies, this investigation enrolled patients un-
the cangrelor infusion would have provided further
dergoing PCI, making the findings more applicable to
important information. Fourth, the use of additional
131
132
Rollini et al.
JACC: CARDIOVASCULAR INTERVENTIONS VOL. 10, NO. 2, 2017 JANUARY 23, 2017:130–2
Switching Between P2Y12 Receptor Inhibitors
platelet function assays would have allowed to
among available agents, on the basis of individual
corroborate the study conclusions.
needs or preference in the safest possible way for our
Overall, these considerations should represent a
patients.
stimulus for further investigation to better elucidate some residual knowledge gaps in this field and define the optimal approach to switch between P2Y 12-
REPRINT REQUESTS AND CORRESPONDENCE: Dr.
inhibiting therapies. This would indeed allow to bet-
Dominick J. Angiolillo, University of Florida College
ter characterize potential DDIs of which clinicians
of Medicine–Jacksonville, 655 West 8th Street, Jack-
need to be aware. Most importantly, this would give
sonville, Florida 32209. E-mail: dominick.angiolillo@
the opportunity to clinicians to choose and switch
jax.ufl.edu.
REFERENCES 1. Rollini F, Franchi F, Angiolillo DJ. Switching P2Y12-receptor inhibitors in patients with coronary artery disease. Nat Rev Cardiol 2016;13:11–27. 2. Franchi F, Angiolillo DJ. Novel antiplatelet agents in acute coronary syndrome. Nat Rev Cardiol 2015;12:30–47.
5. Steg PG, Bhatt DL, Hamm CW, et al. Effect of cangrelor on periprocedural outcomes in percutaneous coronary interventions: a pooled analysis of patient-level data. Lancet 2013;382:1981–92. 6. Judge HM, Buckland RJ, Jakubowski JA, Storey RF. Cangrelor inhibits the binding of the
3. Angiolillo DJ, Schneider DJ, Bhatt DL, et al. Pharmacodynamic effects of cangrelor and clopidogrel: the platelet function substudy from the Cangrelor Versus Standard Therapy to Achieve Optimal Management of Platelet Inhibition (CHAMPION) trials. J Thromb Thrombolysis 2012;34:44–55.
active metabolites of clopidogrel and prasugrel to P2Y12 receptors in vitro. Platelets 2016;27: 191–5.
4. Steinhubl SR, Oh JJ, Oestreich JH, et al. Transitioning subjects from cangrelor to clopidogrel: pharmacodynamic evidence of a competitive effect. Thromb Res 2008;121:527–34.
Artery Dis 2015;26:42–8.
7. Schneider DJ, Seecheran N, Raza SS, Keating FK, Gogo P. Pharmacodynamic effects during the transition between cangrelor and prasugrel. Coron 8. Schneider DJ, Agarwal Z, Seecheran N, Keating FK, Gogo P. Pharmacodynamic effects during the transition between cangrelor and
ticagrelor. J Am Coll Cardiol Intv 2014;7: 435–42. 9. Hochholzer W, Kleiner P, Younas I, et al. Randomized comparison of oral P2Y12-receptor inhibitor loading strategies for transitioning from cangrelor: the ExcelsiorLOAD2 trial. J Am Coll Cardiol Intv 2017;10:121–9. 10. Farid NA, Kurihara A, Wrighton SA. Metabolism and disposition of the thienopyridine antiplatelet drugs ticlopidine, clopidogrel, and prasugrel in humans. J Clin Pharmacol 2010;50: 126–42.
KEY WORDS cangrelor, drug-drug interactions, prasugrel, switching, ticagrelor